Fare classes with obscured demand

ABSTRACT

A computer-based system for unobscuring and/or unconstraining demand is disclosed. Via use of the system, actual airline seat bookings may be restated in an unobscured and/or unconstrained form, facilitating improved demand forecasts for subsequent seat bookings. In this manner, seat protects may be better allocated to align with actual demand, thus increasing revenue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, claims priority to and thebenefit of, U.S. Ser. No. 15/654,240 filed Jul. 19, 2017 and entitled“AIRLINE DEMAND FORECASTING UTILIZING UNOBSCURING AND UNCONSTRAINING.”The '240 application is a continuation of, claims priority to and thebenefit of, U.S. Ser. No. 13/791,672 filed on Mar. 8, 2013, (aka U.S.Pat. No. 9,727,940, which issued Aug. 8, 2017) and entitled “DEMANDFORECASTING SYSTEMS AND METHODS UTILIZING UNOBSCURING ANDUNCONSTRAINING”. Both are hereby incorporated by reference in theirentirety for all purposes.

TECHNICAL FIELD

The present disclosure generally relates to forecasting, and moreparticularly, to analysis methods and tools suitable for use inconnection with yield management systems, inventory control systems,revenue management systems, and the like.

BACKGROUND

The transportation services industry, and particularly the airlineindustry, is often associated with high costs and varying degrees ofprofitability. As a result, airlines often seek new sources of income(e.g., ala carte pricing for additional services) and innovative ways toincrease revenues and/or reduce costs (e.g., optimizing existingprocesses). One such method of increasing revenues involves pricingseats on a particular flight in groups or “classes”. Bookings inhigher-fare classes are typically given priority in order to increasethe total revenue associated with a flight.

However, in many instances, a passenger may book a reservation at alower price point than the maximum amount the passenger would be willingto pay for that seat. The difference in price between the higher-pricedticket and the purchased ticket represents foregone revenue for theairline. Accordingly, improved forecasting and analysis methods remaindesirable, for example, for use in systems configured to allow airlinesto book seats at prices more closely associated with the maximum amounta passenger is willing to pay.

SUMMARY

In an embodiment, a method comprises accessing, by a processor forunobscuring demand, a bookings table representing seat bookings for aflight. The seat bookings occurred during a first time period, and theseat bookings are grouped into a plurality of fare classes. The methodfurther comprises: determining, by the processor, which fare classes inthe plurality of fare classes have demand that is obscured; calculating,by the processor, the unobscured demand for at least one fare class inthe plurality of fare classes; converting, by the processor, theunobscured demand for the at least one fare class into integer valuesrepresenting seat bookings in the respective fare classes; and updating,by the processor, the bookings table with the integer values to form anunobscured bookings table.

In another embodiment, a method comprises: accessing, by a processor forunconstraining demand, an unobscured bookings table representingunobscured demand for seat bookings in a plurality of fare classes;determining, by the processor, the fare classes in the plurality of fareclasses for which demand is constrained; calculating, by the processor,the unconstrained demand for each constrained fare class in theplurality of fare classes; converting, by the processor, theunconstrained demand for each fare class into integer valuesrepresenting seat bookings in the respective fare classes; and updating,by the processor, the unobscured bookings table with the integer valuesto form an unconstrained bookings table.

The contents of this summary section are provided only as a simplifiedintroduction to the disclosure, and are not intended to be used to limitthe scope of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the following description, appended claims, andaccompanying drawings:

FIG. 1A is a block diagram illustrating exemplary forecasting systemcomponents in accordance with various embodiments;

FIG. 1B illustrates exemplary approaches for yield management, includingreducing spiral down in accordance with various embodiments;

FIG. 2A illustrates an exemplary unobscuring method in accordance withvarious embodiments;

FIG. 2B illustrates an exemplary unobscuring and unconstraining methodin accordance with various embodiments;

FIG. 2C illustrates the result of an exemplary unobscuring method inaccordance with various embodiments;

FIG. 3A illustrates an exemplary unconstraining method in accordancewith various embodiments;

FIG. 3B illustrates the result of an exemplary unconstraining method inaccordance with various embodiments;

FIG. 4A illustrates an exemplary fare adjustment method in accordancewith various embodiments;

FIG. 4B illustrates a chart of exemplary price-oriented bookings andproduct-oriented bookings in a bookings table in accordance with variousembodiments;

FIG. 4C illustrates seat allocation in a fare class in accordance withan exemplary fare adjustment method, in accordance with variousembodiments; and

FIG. 5 illustrates a method for prime class remapping in accordance withvarious embodiments.

DETAILED DESCRIPTION

Principles of the present disclosure can reshape the way organizationsforecast, calculate, and/or implement decisions, such as revenuemanagement and/or cost reduction strategies. For example, principles ofthe present disclosure enable airlines to:

-   -   formulate more accurate answers to the question, “How many (and        what type) of bookings would have been realized if a particular        fare class (or set of fare classes) were closed?”;    -   formulate more accurate answers to the question, “How many (and        what type) of bookings would have been realized if a particular        fare class (or set of fare classes) were opened?”;    -   realize bookings that are more closely aligned with the highest        price a customer is actually willing to pay for a particular        seat;    -   adjust, at discrete intervals and/or in real-time, demand        forecasts for particular fare classes and implement fare class        openings/closings in order to increase and/or maximize revenue;        stated generally, principles of the present disclosure enable        airlines to reduce forecasting errors and account for        interdependence of demand between fare classes.

While the present disclosure discusses airlines and “flights” forpurposes of convenience and illustration, one of skill in the art willappreciate that the forecasting methods, systems, and tools disclosedherein are broadly applicable, for example to any transportationindustry, such as buses, cruise ships, passenger trains, and the like.

Various embodiments of principles of the present disclosure employforecasting, statistical analysis and/or optimization techniques. Formore information regarding such techniques refer to, for example: “TheTheory and Practice of Revenue Management” (International Series inOperations Research & Management Science) by Kalyan T. Talluri andGarrett J. van Ryzin; “Using Multivariate Statistics (5th Edition)” byBarbara G. Tabachnick and Linda S. Fidell; and “Introduction toOperations Research” by Friedrich S. Hiller and Gerald J. Lieberman,McGraw-Hill 7th edition, Mar. 22, 2002; the contents of which are eachhereby incorporated by reference in their entireties.

In various embodiments, exemplary forecasting systems include a userinterface (“UI”), software modules, logic engines, various databases,interfaces to systems and tools, and/or computer networks. Whileexemplary forecasting systems may contemplate upgrades orreconfigurations of existing processing systems, changes to existingdatabases and system tools are not necessarily required by principles ofthe present disclosure.

The benefits provided by principles of the present disclosure include,for example, increased revenue, increased forecasting accuracy, lowercosts, increased seat utilization, increased customer good will,increased planning and operational efficiency, and increased employeemorale. For example, a revenue management organization benefits fromimproved forecasting accuracy and resulting increased revenue. Customersbenefit from booking availability that more closely tracks theirwillingness to pay, increasing the likelihood of a suitable seat andassociated fare being available for them.

As used herein: a “fare class” or “class” refers to a group of airlineseats that are priced similarly to one another.

“Willingness to pay” refers to the highest fare class a customer willpay for a product, such as a seat on a flight (i.e., analogous to areserve price).

“Buy down” refers to a booking being realized in a class that is lowerthan the customer's willingness to pay.

“Spiral down” refers to repeated buy down cycles; when forecasts andseat protects are based on observed bookings rather than willingness topay, leading to future bookings in lower classes.

A “constrained class” is a class where bookings are restricted byavailability in that class.

An “obscured class” is a class where bookings are restricted due toavailability of the same product in a lower fare class.

An “active class” or “observed class” is the lowest class withavailability and bookings. Lower classes are constrained and higherclasses are obscured.

A “parent class” and “child class” are the fare classes directly aboveand below the other, respectively.

A “cohort” is a group of flights having similar characteristics, suchthat statistical information for some (or all) of the flights in thecohort may be utilized to draw inferences regarding one or more flightsin the cohort.

An “entity” may include any individual, software program, business,organization, government entity, web site, system, hardware, and/or anyother entity.

A “user” may include any entity that interacts with a system and/orparticipates in a process.

Turning now to FIG. 1A, in accordance with various embodiments, a user105 may perform tasks such as requesting, retrieving, receiving,updating, analyzing and/or modifying data. User 105 may also performtasks such as initiating, manipulating, interacting with or using asoftware application, tool, module or hardware, and initiating,receiving or sending a communication. User 105 may interface withInternet server 125 via any communication protocol, device or methoddiscussed herein, known in the art, or later developed. User 105 may be,for example, a member of a revenue management organization, a member ofan operations research and systems analysis organization, a downstreamsystem, an upstream system, a third-party system, a systemadministrator, and/or the like.

In various embodiments, a system 101 may include a user 105 interfacingwith a forecasting system 115 by way of a client 110. Forecasting system115 may be a partially or fully integrated system comprised of varioussubsystems, modules and databases. Client 110 comprises any hardwareand/or software suitably configured to facilitate entering, accessing,requesting, retrieving, updating, analyzing and/or modifying data. Thedata may include operational data (e.g., schedules, resources, routes,operational alerts, weather, etc.), passenger data, cost data,forecasts, historical data, verification data, asset (e.g., airplane)data, inventory (e.g., airplane seat) data, legal/regulatory data,authentication data, demographic data, transaction data, or any othersuitable information discussed herein.

Client 110 includes any device (e.g., a computer), which communicates,in any manner discussed herein, with forecasting system 115 via anynetwork or protocol discussed herein. Browser applications compriseInternet browsing software installed within a computing unit or systemto conduct online communications and transactions. These computing unitsor systems may take the form of personal computers, mobile phones,personal digital assistants, mobile email devices, laptops, notebooks,hand-held computers, portable computers, kiosks, and/or the like.Practitioners will appreciate that client 110 may or may not be indirect contact with forecasting system 115. For example, client 110 mayaccess the services of forecasting system 115 through another server,which may have a direct or indirect connection to Internet server 125.Practitioners will further recognize that client 110 may presentinterfaces associated with a software application (e.g., SAS analyticsoftware) or module that are provided to client 110 via application GUIsor other interfaces and are not necessarily associated with or dependentupon internet browsers or internet specific protocols.

User 105 may communicate with forecasting system 115 through a firewall120, for example to help ensure the integrity of forecasting system 115components. Internet server 125 may include any hardware and/or softwaresuitably configured to facilitate communications between the client 110and one or more forecasting system 115 components.

Firewall 120, as used herein, may comprise any hardware and/or softwaresuitably configured to protect forecasting system 115 components fromusers of other networks. Firewall 120 may reside in varyingconfigurations including stateful inspection, proxy based and packetfiltering, among others. Firewall 120 may be integrated as softwarewithin Internet server 125, any other system 101 component, or mayreside within another computing device or may take the form of astandalone hardware component.

Authentication server 130 may include any hardware and/or softwaresuitably configured to receive authentication credentials, encrypt anddecrypt credentials, authenticate credentials, and/or grant accessrights according to pre-defined privileges associated with thecredentials. Authentication server 130 may grant varying degrees ofapplication and/or data level access to users based on informationstored within authentication database 135 and user database 140.Application server 142 may include any hardware and/or software suitablyconfigured to serve applications and data to a connected client 110.

In accordance with various embodiments, forecasting system 115 is usableto increase and/or maximize revenue, manage inventory strategy, generateinputs to other forecasting systems, and/or the like. Continuing toreference FIG. 1A, forecasting system 115 allows communication withcentral data repository (CDR) 150, and with various other databases,tools, UIs and systems (not shown in FIG. 1A). Such systems include, forexample, airline scheduling systems, passenger booking and reservationssystems, revenue management systems, inventory systems, and/or the like.

Forecasting system 115 components are interconnected and communicatewith one another to allow for a completely integrated forecastingsystem. In various embodiments, forecasting system 115 formulates demandforecast models and associated revenue consequences at the class level,seat level, and so forth. Airline reservations systems sell inventorybased at least in part upon the output of forecasting system 115.

In various embodiments, forecasting system 115 modules (e.g.,willingness to pay (WTP) system 145, unobscuring module 146,unconstraining module 147, fare adjustment module 148, prime-class remapmodule 149, and other forecasting system 115 modules not shown in FIG.1A) are software modules configured to enable online functions such assending and receiving messages, receiving query requests, configuringresponses, dynamically configuring user interfaces, requesting data,receiving data, displaying data, executing complex processes,calculations, forecasts, mathematical techniques, workflows and/oralgorithms, prompting user 105, verifying user responses, authenticatingthe user, initiating forecasting system 115 processes, initiating othersoftware modules, triggering downstream systems and processes,encrypting and decrypting, and/or the like. Additionally, forecastingsystem 115 modules may include any hardware and/or software suitablyconfigured to receive requests from client 110 via Internet server 125and application server 142.

Forecasting system 115 modules may be further configured to processrequests, execute transactions, construct database queries, and/orexecute queries against databases within system 101 (e.g., central datarepository (“CDR”) 150), external data sources and/or temporarydatabases. In various embodiments, one or more forecasting system 115modules may be configured to execute application programming interfacesin order to communicate with a variety of messaging platforms, such asemail systems, wireless communications systems, mobile communicationssystems, multimedia messaging service (“MMS”) systems, short messagingservice (“SMS”) systems, and the like.

Forecasting system 115 modules may be configured to exchange data withother systems and application modules, for example an airlinereservation system. In various embodiments, forecasting system 115modules may be configured to interact with other system 101 componentsto perform complex calculations, retrieve additional data, format datainto reports, create XML representations of data, construct markuplanguage documents, construct, define or control UIs, and/or the like.Moreover, forecasting system 115 modules may reside as standalonesystems or tools or may be incorporated with the application server 142or any other forecasting system 115 component as program code. As one ofordinary skill in the art will appreciate, forecasting system 115modules may be logically or physically divided into varioussubcomponents, such as a workflow engine configured to evaluatepredefined rules and to automate processes.

In addition to the components described above, forecasting system 115may further include one or more of the following: a host server or othercomputing systems including a processor for processing digital data; amemory coupled to the processor for storing digital data; an inputdigitizer coupled to the processor for inputting digital data; anapplication program stored in the memory and accessible by the processorfor directing processing of digital data by the processor; a displaydevice coupled to the processor and memory for displaying informationderived from digital data processed by the processor; a plurality ofdatabases, and/or the like.

As will be appreciated by one of ordinary skill in the art, one or moresystem 101 components may be embodied as a customization of an existingsystem, an add-on product, upgraded software, a stand-alone system(e.g., kiosk), a distributed system, a method, a data processing system,a device for data processing, and/or a computer program product.Accordingly, individual system 101 components may take the form of anentirely software embodiment, an entirely hardware embodiment, or anembodiment combining aspects of both software and hardware. Furthermore,individual system 101 components may take the form of a computer programproduct on a computer-readable storage medium having computer-readableprogram code means embodied in the storage medium. Any suitablecomputer-readable storage medium may be utilized, including magneticstorage devices (e.g., hard disks), optical storage devices, (e.g.,DVD-ROM, CD-ROM, etc.), electronic storage devices (e.g., flash memory),and/or the like.

Client 110 may include an operating system (e.g., Windows, UNIX, Linux,Solaris, MacOS, iOS, Windows Mobile OS, Windows CE, Palm OS, Symbian OS,Blackberry OS, J2ME, etc.) as well as various conventional supportsoftware and drivers typically associated with mobile devices and/orcomputers. Client 110 may be in any environment with access to anynetwork, including both wireless and wired network connections. Invarious embodiments, access is through a network or the Internet througha commercially available web-browser software package. Client 110 andforecasting system 115 components may be independently, separately orcollectively suitably coupled to the network via data links whichinclude, for example, a connection to an Internet Service Provider (ISP)over the local loop as is typically used in connection with standardwireless communications networks and/or methods, such as modemcommunication, cable modem, satellite networks, ISDN, digital subscriberline (DSL), and/or the like. In various embodiments, any portion ofclient 110 may be partially or fully connected to a network using awired (“hard wire”) connection. As those skilled in the art willappreciate, client 110 and/or any of the system components may includewired and/or wireless portions.

Internet server 125 may be configured to transmit data to client 110within markup language documents. “Data” may include encompassinginformation such as commands, messages, transaction requests, queries,files, data for storage, and/or the like in digital or any other form.Internet server 125 may operate as a single entity in a singlegeographic location or as separate computing components located togetheror in separate geographic locations. Further, Internet server 125 mayprovide a suitable web site or other Internet-based graphical userinterface, which is accessible by users (such as user 105). In variousembodiments, Microsoft Internet Information Server (IIS), MicrosoftTransaction Server (MTS), and Microsoft SQL Server, are used inconjunction with a Microsoft operating system, Microsoft NT web serversoftware, a Microsoft SQL Server database system, and a MicrosoftCommerce Server. In various embodiments, the well-known “LAMP” stack(Linux, Apache, MySQL, and PHP/Perl/Python) are used to enableforecasting system 115. Additionally, components such as Access orMicrosoft SQL Server, Oracle, Sybase, InterBase, etc., may be used toprovide an Active Data Object (ADO) compliant database managementsystem.

Like Internet server 125, application server 142 may communicate withany number of other servers, databases and/or components through anymeans known in the art. Further, application server 142 may serve as aconduit between client 110 and the various systems and components offorecasting system 115. Internet server 125 may interface withapplication server 142 through any means known in the art including aLAN/WAN, for example. Application server 142 may further invoke softwaremodules, such as WTP system 145, automatically or in response to user105 requests.

Any of the communications, inputs, storage, databases or displaysdiscussed herein may be facilitated through a web site having web pages.The term “web page” as it is used herein is not meant to limit the typeof documents and applications that may be used to interact with theuser. For example, a typical web site may include, in addition tostandard HTML documents, various forms, Java applets, JavaScript, activeserver pages (ASP), common gateway interface scripts (CGI), Flash filesor modules, FLEX, ActionScript, extensible markup language (XML),dynamic HTML, cascading style sheets (CSS), helper applications,plug-ins, and/or the like. A server may include a web service thatreceives a request from a web server, the request including a URL (e.g.,http://yahoo.com/) and/or an internet protocol (“IP”) address. The webserver retrieves the appropriate web pages and sends the data orapplications for the web pages to the IP address. Web services areapplications that are capable of interacting with other applicationsover a communications means, such as the Internet. Web services aretypically based on standards or protocols such as XML, SOAP, WSDL andUDDI. Web services methods are well known in the art, and are covered inmany standard texts. See, e.g., Alex Nghiem, IT Web Services: A Roadmapfor the Enterprise (2003).

Continuing to reference FIG. 1A, illustrated are databases that areincluded in various embodiments. An exemplary list of various databasesused herein includes: an authentication database 135, a user database140, CDR 150 and/or other databases that aid in the functioning of thesystem. As practitioners will appreciate, while depicted as separateand/or independent entities for the purposes of illustration, databasesresiding within system 101 may represent multiple hardware, software,database, data structure and networking components. Furthermore,embodiments are not limited to the databases described herein, nor doembodiments necessarily utilize each of the disclosed databases.

Authentication database 135 may store information used in theauthentication process such as, for example, user identifiers,passwords, access privileges, user preferences, user statistics, and thelike. User database 140 maintains user information and credentials forforecasting system 115 users (e.g., user 105).

In various embodiments, CDR 150 is a data repository that may beconfigured to store a wide variety of comprehensive data for forecastingsystem 115. While depicted as a single logical entity in FIG. 1A, thoseof skill in the art will appreciate that CDR 150 may, in variousembodiments, consist of multiple physical and/or logical data sources.In various embodiments, CDR 150 stores operational data, schedules,resource data, asset data, inventory data, personnel information, routesand route plans, station (e.g., airports or other terminals) data,operational alert data, weather information, passenger data, reservationdata, cost data, optimization results, booking class data, forecasts,historical data, verification data, authentication data, demographicdata, legal data, regulatory data, transaction data, security profiles,access rules, content analysis rules, audit records, predefined rules,process definitions, financial data, and the like. For example, invarious exemplary embodiments a data source or component database of CDR150 includes information such as flight key (e.g., flight number, flightdate, origin, and destination), forecast timeband, days until departure(“Rel Day”), class demand, a class posted indicator (i.e., an indicationof whether or not a class was available for sale during a time period),class bookings information, class average fare, active class by Rel Day,seasonal identifiers, sponsor identifiers, and/or the like.

Any databases discussed herein may include relational, hierarchical,graphical, or object-oriented structure and/or any other databaseconfigurations. Common database products that may be used to implementthe databases include DB2 by IBM (Armonk, N.Y.), various databaseproducts available from Oracle Corporation (Redwood Shores, Calif.),Microsoft Access or Microsoft SQL Server by Microsoft Corporation(Redmond, Wash.), MySQL by MySQL AB (Uppsala, Sweden), or any othersuitable database product. Moreover, the databases may be organized inany suitable manner, for example, as data tables or lookup tables. Eachrecord may be a single file, a series of files, a linked series of datafields or any other data structure. Association of certain data may beaccomplished through any desired data association technique such asthose known or practiced in the art. For example, the association may beaccomplished either manually or automatically. Automatic associationtechniques may include, for example, a database search, a databasemerge, GREP, AGREP, SQL, using a key field in the tables to speedsearches, sequential searches through all the tables and files, sortingrecords in the file according to a known order to simplify lookup,and/or the like. The association step may be accomplished by a databasemerge function, for example, using a “key field” in pre-selecteddatabases or data sectors. Various database tuning steps arecontemplated to optimize database performance. For example, frequentlyused files such as indexes may be placed on separate file systems toreduce In/Out (“I/O”) bottlenecks.

One skilled in the art will also appreciate that, for security reasons,any databases, systems, devices, servers or other components of system101 may consist of any combination thereof at a single location or atmultiple locations, wherein each database or system includes any ofvarious suitable security features, such as firewalls, access codes,encryption, decryption, compression, decompression, and/or the like.

The systems and methods may be described herein in terms of functionalblock components, screen shots, optional selections and variousprocessing steps. It should be appreciated that such functional blocksmay be realized by any number of hardware and/or software componentsconfigured to perform the specified functions. For example, the systemmay employ various integrated circuit components, e.g., memory elements,processing elements, logic elements, look-up tables, and the like, whichmay carry out a variety of functions under the control of one or moremicroprocessors or other control devices. Similarly, the softwareelements of the system may be implemented with any programming orscripting language such as C, C++, C#, Java, JavaScript, Flash,ActionScript, FLEX, VBScript, Macromedia Cold Fusion, COBOL, MicrosoftActive Server Pages, assembly, PERL, SAS, PHP, awk, Python, VisualBasic, SQL Stored Procedures, PL/SQL, any UNIX shell script, and/orextensible markup language (XML) or the like, with the variousalgorithms being implemented with any combination of data structures,objects, processes, routines or other programming elements. Further, itshould be noted that the system may employ any number of conventionaltechniques for data transmission, signaling, data processing, networkcontrol, and the like. Still further, the system may be used to detector prevent security issues with a client-side scripting language, suchas JavaScript, VBScript or the like.

Software elements may be loaded onto a general purpose computer, specialpurpose computer, or other programmable data processing apparatus toproduce a machine, such that the instructions that execute on thecomputer or other programmable data processing means for implementingthe functions specified in the flowchart block or blocks. These computerprogram instructions may also be stored in a computer-readable memorythat can direct a computer or other programmable data processingapparatus to function in a particular manner, such that the instructionsstored in the computer-readable memory produce an article of manufactureincluding instruction means which implement the function specifiedherein or in flowchart block or blocks. The computer programinstructions may also be loaded onto a computer or other programmabledata processing apparatus to cause a series of operational steps to beperformed on the computer or other programmable apparatus to produce acomputer-implemented process such that the instructions which execute onthe computer or other programmable apparatus provide steps forimplementing the functions specified in the flowchart block or blocks.

Accordingly, functional blocks of the block diagrams and flowchartillustrations support combinations of means for performing the specifiedfunctions, combinations of steps for performing the specified functions,and program instruction means for performing the specified functions. Itwill also be understood that each functional block of the block diagramsand flowchart illustrations, and combinations of functional blocks inthe block diagrams and flowchart illustrations, can be implemented byeither special purpose hardware-based computer systems which perform thespecified functions or steps, or suitable combinations of specialpurpose hardware and computer instructions. Further, illustrations ofthe process flows and the descriptions thereof may make reference touser windows, web pages, web sites, web forms, prompts, etc.Practitioners will appreciate that the illustrated steps describedherein may comprise any number of configurations including the use ofwindows, web pages, web forms, popup windows, prompts and/or the like.It should be further appreciated that the multiple steps as illustratedand described may be combined into single web pages and/or windows buthave been expanded for the sake of simplicity. In other cases, stepsillustrated and described as single process steps may be separated intomultiple web pages and/or windows but have been combined for simplicity.

With continued reference to FIG. 1A, in various embodiments, user 105logs onto an application (e.g., a module) and Internet server 125 mayinvoke an application server 142. Application server 142 invokes logicin the forecasting system 115 modules by passing parameters relating touser's 105 requests for data. Forecasting system 115 manages requestsfor data from forecasting system 115 modules and/or communicates withsystem 101 components. Transmissions between user 105 and Internetserver 125 may pass through a firewall 120 to help ensure the integrityof forecasting system 115 components. Practitioners will appreciate thatexemplary embodiments may incorporate any number of security schemes ornone at all. In various embodiments, Internet server 125 receivesrequests from client 110 and interacts with various other system 101components to perform tasks related to requests from client 110.

Internet server 125 may invoke an authentication server 130 to verifythe identity of user 105 and assign roles, access rights and/orpermissions to user 105. In order to control access to the applicationserver 142 or any other component of forecasting system 115, Internetserver 125 may invoke an authentication server 130 in response to user105 submissions of authentication credentials received at Internetserver 125. In response to a request to access system 101 being receivedfrom Internet server 125, Internet server 125 determines ifauthentication is required and transmits a prompt to client 110. User105 enters authentication data at client 110, which transmits theauthentication data to Internet server 125. Internet server 125 passesthe authentication data to authentication server 130 which queries theuser database 140 for corresponding credentials. In response to user 105being authenticated, user 105 may access various applications and theircorresponding data sources.

With reference now to FIGS. 1A and 1B, various prior approaches toairline seat demand forecasting have suffered from various shortcomings,for example susceptibility to spiral down. Prior demand forecasts weretypically based on actual seat bookings, leading to repeated cycles offare deterioration as additional groups of lower priced seats werereleased for sale based on inaccurate demand estimates. Additionally,prior demand forecasts typically assumed, inaccurately, that demand fora particular fare class was independent of demand for other fareclasses.

In contrast, principles of the present disclosure contemplate approachesto demand forecasting, wherein interrelationships among demand for fareclasses are taken into account. For example, interrelationships amongdemand for fare classes may arise anytime that there is more than onevalid fare for a particular seat on a flight. In various embodiments,airline seat demand forecasting systems and methods are configured toconsider that a particular fare class, while open, may be effectivelyclosed due to seat availability in a lower fare class or classes. Suchopen fare classes may be referred to as “obscured”, as demand for suchfare classes is not readily apparent. Principles of the presentdisclosure may be utilized to “unobscure” (or otherwise improve) demandforecasts for such fare classes.

In various embodiments, unobscuring module 146 is configured to generateand/or modify an improved demand forecast for a fare class or set offare classes. Moreover, unobscuring module 146 may be configured torevise and/or modify historical booking information to representunobscured booking information. Stated generally, unobscuring module 146is configured to provide an answer to the question: “For a particularfare class F_(i), how many bookings would have been taken if the fareclasses below F_(i) were closed?”

Unobscuring module 146 may utilize historical data regarding seatbookings for a prior period of time, for example the prior 52 weeks ofbooking information. Moreover, any suitable amount of historical datamay be utilized. Unobscuring module 146 may also utilize informationsuch as flight key (e.g., flight number, flight date, origin, anddestination), forecast timeband, days until departure (“Rel Day”), aclass posted indicator, class bookings information, seasonalidentifiers, sponsor identifiers, and/or the like.

In various embodiments, unobscuring module 146 is configured to generatepredicted booking information that differs from actual observedbookings. In various embodiments, unobscuring module 146 generatesdemand forecasts directly; in other exemplary embodiments, predictedbooking information generated by unobscuring module 146 may be deliveredto other electronic systems (for example, Passenger Revenue OptimizationSystem or “PROS” offered by PROS Holdings, Inc.) in lieu of actualobserved booking information, in order to generate improved demandforecasts.

In various embodiments, unobscuring module 146 processes net individualseat bookings that occurred between a first point in time (which may bea “data collection point” or DCP) and a second point in time (which maybe, but is not necessarily, a second DCP). Table 1A illustrates anexemplary snapshot of total bookings for a particular example Flight244, scheduled for travel from Detroit (DTW) to Phoenix (PHX). In Table1A, total bookings are represented as of a particular DCP (for example,at example DCP 19, which is a point in time 8 days prior to thescheduled departure of Flight 244). In Table 1A, total bookings arelisted by fare class in descending price order.

TABLE 1A Total bookings for Flight 244 as of DCP 19 Total Bookings toFare Class Date Q 1 N 1 V 8 W 15 L 9 S 7 T 19 G 7 K 15 U 7 E 5 R 0

Continuing this example, in the time period between the current DCP 19and the prior DCP 18, the following new bookings for Flight 244occurred:

TABLE 1B New Bookings for Flight 244 Occurring Between DCP 18 and DCP 19Fare Class New Bookings Q 0 N 0 V 0 W 3 L 0 S 0 T 1 G 0 K 4 U 0 E 0 R 0

To facilitate improved demand forecasting approaches and/or tofacilitate interactions with other components of system 101 (forexample, external systems and databases 160), the booking information inTables 1A and/or 1B may also be considered in “top-down” form, whereinthe booking number associated with each fare class represents the sum ofbookings in that fare class as well as all higher fare classes.Converting the new booking information in Table 1B to top-down form,Table 1C is obtained:

TABLE 1C New Bookings Fare Class New Bookings (Top-Down) Q 0 0 N 0 0 V 00 W 3 3 L 0 3 S 0 3 T 1 4 G 0 4 K 4 8 U 0 8 E 0 8 R 0 8

With the example data formatted as illustrated in Table 1C, a baselineassumption about bookings for this example Flight 244 can be inferred,namely: if, during the current period (i.e., between DCP 18 and DCP 19),fare classes U through R were not open for bookings, Flight 244 wouldhave received at least 8 bookings (i.e., a number equal to the actualbookings). However, if fare class K was not open for bookings, Flight244 might still have received the four bookings taken in fare class K(i.e., in fare class G or another higher class); however, it is alsopossible that only three, or two, or one, or zero of the observed Kclass bookings would have occurred. Because of this uncertainty, theactual demand for bookings in fare class G may be considered to beobscured. All fare classes above class G may also be consideredobscured.

With reference now to FIGS. 2A and 2B, in accordance with variousembodiments, unobscuring module 146 is configured to implement a method200 for unobscuring demand. In method 200, unobscuring module 146 mayoperate class-by-class, for example from the lowest price class throughthe highest price class, in order to provide a revised demand forecastand/or unobscured booking information useable to reduce and/or minimizeforecasting errors associated with obscured demand.

Unobscuring module 146 and/or method 200 may be utilized on any suitabletime schedule, as desired. For example, unobscuring module 146 may beoperable on a weekly basis, on a daily basis, on an hourly basis, on a“triggered” basis (for example, each time a trigger event occurs, suchas a booking or series of bookings), after collection of data associatedwith a DCP, and/or the like.

In various embodiments, and with reference to FIG. 2A, in method 200booking information for a particular flight is converted into top-downformat (step 210). Beginning with the lowest fare class as the “currentclass”, the mean and standard deviation of top-down bookings in thecurrent class is computed (step 220). In various exemplary embodiments,statistical information from the cohort to which the particular flightbelongs is used to generate the mean and standard deviation of top-downbookings in the current class. A normal distribution may initially beassumed; however, other suitable distributions may also be utilized. Ifthe current class is obscured, a suitable estimation algorithm, forexample an expectation maximization (EM) algorithm 235 (not shown in thefigures), is applied in an iterative fashion to calculate an unobscureddemand for the current class (step 230). In various embodiments, EMalgorithm 235 comprises an algorithm identical or substantiallyequivalent to:

${E\left( X \middle| {a < X < b} \right)} = {\mu + {\frac{{\varphi \left( \frac{a - \mu}{\sigma} \right)} - {\varphi \left( \frac{b - \mu}{\sigma} \right)}}{{\Phi \left( \frac{b - \mu}{\sigma} \right)} - {\Phi \left( \frac{a - \mu}{\sigma} \right)}}\sigma}}$

In an exemplary embodiment, EM algorithm 235 may be written in anon-normalized form as:expBkgs=mean+(stdev*stdev)*(pdfLower−pdfUpper)/(cdfUpper−cdfLower);where:

expBkgs is the expectation of bookings in the current class; i.e. theunobscured bookings;

upperBound is the upper bound of the unobscured bookings in the currentclass, which may be equivalent to the unobscured bookings in the childclass;lowerBound is the lower bound of the unobscured bookings in the currentclass, which may be equivalent to the actual top-down cumulativebookings taken in the current class;mean: the mean of the bookings (unobscured, unconstrained, and/orunobscured and unconstrained) for the current class in the appropriatecohort to which the current flight belongs;stdev: the standard deviation of the bookings (unobscured,unconstrained, and/or unobscured and unconstrained) for the currentclass in the appropriate cohort to which the current flight belongs;cdfUpper is the cumulative distribution function of the upper bound;cdfLower is the cumulative distribution function of the lower bound;pdfUpper is the probability density function of the upper bound; andpdfLower is the probability density function of the lower bound.

In various embodiments, in method 200 the unobscured demand for thecurrent class is used as the upper bound for unobscured demand for theparent class. The process is repeated for each parent class (step 240)until the unobscured demand for the highest fare class is obtained.

Because airline seats are booked on an integer basis (i.e, a partialseat booking is not possible), the unobscured demand values may berounded or otherwise converted into discrete values (step 250); however,it will be appreciated that (i) when unobscuring module 146 is utilizedin connection with other systems configured to accept fractional demandvalues, and/or (ii) when unobscuring module 146 is utilized inconnection with demand forecasting associated with products and/orservices amendable to fractional demand modeling, step 250 may beomitted. An updated demand forecast and/or unobscured bookinginformation is generated (step 260).

In various exemplary embodiments, statistical information from a cohortor cohorts to which the current flight belongs may be utilized inunobscuring module 146 and/or method 200. A cohort may comprise anysuitable number of flights; moreover, any suitable amount of historicaldata for the cohort may be utilized. In various exemplary embodiments, acohort comprises between about 25 flights and about 75 flights. In oneexemplary embodiment, a cohort comprises 50 flights. In variousexemplary embodiments, between one month of historical information andtwo years of historical information (or 3+ years of historicalinformation, for seasonal effects) may be utilized to conductstatistical assessments of the cohort. In one exemplary embodiment, 52weeks of historical information are utilized to make a statisticalassessment of the cohort.

With continued reference to FIG. 2B, method 200 may be applied to theexemplary booking data for Flight 244 provided in Table 1C. For eachfare class, it is known that the minimum demand in that fare class isthe top-down value of bookings in that class. Accordingly, with respectto the lowest fare class, R class, the lower bound on demand is theobserved topdown bookings (i.e., 8). The upper bound is based on theclass below class R (i.e., the child class). However, because class R isthe lowest fare class, it has no child class, so the expected demand forR class, DEM_(R), is bounded as follows: 8≤DEM_(R)≤8. Moving up to theparent class of class R, class E, DEM_(R) becomes the new upper boundfor DEM_(E). Therefore, 8≤DEM_(E)≤8. Classes U and K follow in similarfashion.

In this example, G class is the first class for which demand isconsidered to be obscured. Here, 4≤DEM_(G)≤8. The lower bound, 4, is theobserved topdown bookings in class G; the upper bound, 8, is DEM_(K),the expected demand in K class (the child class of class G). An EMalgorithm may be utilized to solve for DEM_(G), for example asillustrated in FIG. 2C.

Using an exemplary EM algorithm, for example an iterative algorithmapplied until a convergent solution is reached, and using appropriateinformation from the cohort of the example flight, values for G classare calculated as follows: Mean=8.48, Std. Dev.=3.32, and DEM_(G)=6.28.Stated differently, when applied to our exemplary data for exampleFlight 244, method 200 predicts that in the current period, 6.28 personswould have booked in G class if K class seating had not been available.Repeating the process for each remaining class, using information fromthe cohort as appropriate, we obtain:

4≤DEM_(T)≤6.28; Mean=8.09, Std. Dev.=3.11, and DEM_(T)=5.27.

3≤DEM_(S)≤5.27; Mean=6.58, Std. Dev.=2.84, and DEM_(S)=4.26.

3≤DEM_(L)≤4.46; Mean=3.46, Std. Dev.=1.33, and DEM_(L)=3.62.

3≤DEM_(W)≤3.62; Mean=3.13, Std. Dev.=1.54, and DEM_(W)=3.31.

0≤DEM_(V)≤3.31; Mean=0.67, Std. Dev.=0.30, and DEM_(V)=0.67.

0≤DEM_(N)≤0.67; Mean=0.09, Std. Dev.=0.03, and DEM_(N)=0.10.

At this point, it will be appreciated that while the process maycontinue for each higher fare class (i.e., class Q), the process mayalso be terminated at this point, as the expected demand for all higherfare classes is approximately zero.

The expected demand values generated above for each fare class may beconverted into integers, for example via simple rounding. Other suitableinteger conversion approaches may be utilized. The results of simplerounding are shown in Table 1D:

TABLE 1D Expected Demand, Expected Demand Rounded Fare Class (Top-Down)(Top-Down) Q N/A 0 N 0.10 0 V 0.67 1 W 3.31 3 L 3.62 4 S 4.26 4 T 5.27 5G 6.28 6 K 8.00 8 U 8.00 8 E 8.00 8 R 8.00 8

To eliminate double counting, the expected demand values may beconverted out of top-down format into a discrete format. Additionally,each booking represented in the expected demand may be allocated to anysuitable fare class; however, in various embodiments each booking isallocated to the highest fare class that can claim it, as shown in Table1E:

TABLE 1E Expected Demand, Rounded Expected Demand, Fare Class (Top-Down)Discrete Q 0 0 N 0 0 V 1 1 W 3 2 L 4 1 S 4 0 T 5 1 G 6 1 K 8 2 U 8 0 E 80 R 8 0

Continuing with the example data at DCP 19 for exemplary Flight 244, theexpected or “unobscured” demand for all fare classes may be compared tothe actual bookings, as shown in Table 1F:

TABLE 1F New Bookings Expected Demand Difference, Actual to Fare Class(Actual) (Discrete) Expected Q 0 0 0 N 0 0 0 V 0 1 +1 W 3 2 −1 L 0 1 +1S 0 0 0 T 1 1 0 G 0 1 +1 K 4 2 −2 U 0 0 0 E 0 0 0 R 0 0 0

In various embodiments, the expected demand information output by method200 and/or unobscuring module 146 may be combined with previouslycalculated expected demand information (for example, expected demandinformation calculated for a prior DCP and/or multiple prior DCPs)and/or with prior actual booking information, and the combined demandinformation may be utilized as an input into an external forecastingsystem. It will be appreciated that in instances when a flight is onlypartially booked (i.e., when many seats on a flight remain open), theoutput of unobscuring module 146 may result in only minor revisionsand/or updates to a demand forecast, a seat protection strategy, and/orthe like; however, when supply and demand levels are close to oneanother (or when demand exceeds supply), the output of unobscuringmodule 146 may result in significant changes to a demand forecast, aseat protection strategy, and/or the like.

Unobscuring module 146 (and/or method 200) may also be configured toutilize weighting factors (for example, seasonal adjustments, and/or thelike) to further refine demand estimates. Additionally, bookinginformation for holidays or other unusual dates may be considered to beoutliers, and associated booking information may be ignored and/orminimally weighted in unobscuring module 146 and/or method 200.

In additional exemplary embodiments, unobscuring module 146 may takeadditional passenger information factors into account, for examplepassenger name record (“PNR”) characteristics. Based at least in part onPNR characteristics, unobscuring module 146 may estimate how likely aparticular passenger is to “buy down” when booking a seat, and thelikelihood of buy-down may be utilized to refine and/or modify theoutput of unobscuring module 146.

Via use of unobscuring module 146 and/or method 200, demand may be moreaccurately forecasted. Consequently, improved fare class opening/closingdecisions may be made.

In addition to utilizing unobscuring module 146, forecasting system 115may be configured to utilize unconstraining module 147 (and/or method300) to create, revise, and/or modify demand forecasts and/or togenerate unconstrained demand information. Stated generally,unconstraining module 147 is configured to provide an answer to thequestion: “How many bookings would have been taken if a particular fareclass F_(NEW) was opened?”

Often, a fare class F_(NEW) is opened partway through the currentperiod, for example the period of time between a first DCP and a secondDCP (or other interval of time over which statistical assessment isdesirable). Stated another way, often a newly opened fare class F_(NEW)was open for bookings for only a portion of a time period for whichbooking information is available. It will be appreciated that therefore,there is at least a possibility that additional bookings would have beenrealized in class F_(NEW) if class F_(NEW) was open for bookings for theentirety of the current period. Because a potential exists for deniedbookings in class F_(NEW), class F_(NEW) may be considered to be“constrained”. Accordingly, the number of bookings that might have beenrealized in class F_(NEW) is not readily apparent.

In various exemplary embodiments, and with reference now to FIGS. 1A and3A, to address this issue unconstraining module 147 is configured toutilize method 300 to obtain unconstrained demand information, forexample unconstrained demand information associated with a particularflight. In various embodiments, unconstraining module 147 is configuredto generate predicted booking information that differs from actualobserved bookings. In certain exemplary embodiments, unconstrainingmodule 147 generates demand forecasts directly; in other exemplaryembodiments, predicted booking information generated by unconstrainingmodule 147 may be delivered to other electronic systems (for example,PROS) in lieu of actual observed booking information, in order togenerate improved demand forecasts.

Unconstraining module 147 and/or method 300 may be utilized on anysuitable time schedule, as desired. For example, unconstraining module147 may be operable on a weekly basis, on a daily basis, on an hourlybasis, on a “triggered” basis (for example, each time a trigger eventoccurs, such as a booking or series of bookings), after collection ofdata associated with a DCP, and/or the like. In various embodiments,unconstraining module 147 is operable subsequent to operation ofunobscuring module 146.

With reference now to FIG. 3A, in various embodiments, in method 300 anunobscured booking table containing unobscured demand information isutilized as an input (step 310). Constrained fare classes are identified(step 320). For each constrained fare class, the correspondingunobscured demand information is converted to unconstrained demandinformation (step 330), for example by utilizing statistical informationfrom the cohort to which the current flight belongs. In variousexemplary embodiments, the statistical information from the cohortcomprises an evaluation of a data set of truncated histories (i.e.,historical information for previous constrained and unconstrainedclasses in the cohort); stated another way, the statistical informationfrom the cohort comprises a comparison of the current constrained fareclass to overall statistical information for the current fare class inthe cohort as a whole.

Because airline seats are booked on an integer basis (i.e, a partialseat booking is not possible), the unconstrained demand information maybe rounded or otherwise converted into discrete values (step 340);however, it will be appreciated that (i) when unconstraining module 147is utilized in connection with other systems configured to acceptfractional demand values, and/or (ii) when unconstraining module 147 isutilized in connection with demand forecasting associated with productsand/or services amendable to fractional demand modeling, step 340 may beomitted. An updated demand forecast and/or unconstrained booking tableis generated (step 350).

Unconstraining module 147 (and/or method 300) may also be configured toutilize weighting factors (for example, seasonal adjustments, and/or thelike) to further refine demand estimates. Additionally, bookinginformation for holidays or other unusual dates may be considered to beoutliers, and associated booking information may be ignored and/orminimally weighted in unconstraining module 147 and/or method 300.

Principles of operation of unconstraining module 147 and/or method 300are illustrated in the example bookings shown in Table 3A. Table 3Aillustrates new bookings for an example Flight 344, which received 10new bookings over a particular interval, for example the time between afirst DCP and a second DCP:

TABLE 3A New Bookings for Flight 344 in the Current Period New BookingsFare Class New Bookings (Top-Down) S 0 0 T 1 1 G 3 4 K 4 8 U 2 10 E 0 10R 0 10

In the example illustrated in Table 3A, fare classes K, U, E, and R wereopened for bookings partway through the current period (i.e., classesK,U,E,R, were closed for bookings for at least part of the currentperiod). Classes K, U, E, R, are shown as underlined in Table 3A toillustrate that these fare classes were opened during the currentperiod.

For this example, it can be seen that if classes U, E, and R were openfor the entire current period, at least 10 bookings would have occurred.Additionally, if classes U, E, and R, were not opened, the two bookingsthat occurred in class U might have occurred in class K (however, it isalso possible that only one, or none, might have occurred). Accordingly,class K may be considered to be obscured as discussed hereinabove.Additionally, because class K was open for bookings for only a portionof the current period, class K is also considered to be “constrained”.

In accordance with principles of the present disclosure, unobscuringmodule 146 may be utilized to determine the unobscured demand for anobscured fare class or classes in this example, such as unobscureddemand DEM_(K) for class K. In accordance with unobscuring principlesdisclosed hereinabove, it can be seen that 8≤DEM_(K)≤10. Via use ofunobscuring module 146, DEM_(K) is determined to be 9.05.

Because example class K was opened for bookings during the currentperiod, class K is constrained. Unobscured demand DEM_(K) (in fractionalor integer form) is utilized as an input to unconstraining module 147and/or method 300 to obtain unconstrained and unobscured demand_(U)DEM_(K) for class K. Via operation of unconstraining module 147,_(U)DEM_(K) is determined to be 10.66, for example as illustrated inFIG. 3B. Stated another way, class K would have been expected to receive10.66 bookings if class K had been open for bookings for the entirecurrent period. A similar approach may be employed to determine_(U)DEM_(U), and similar demand forecasting inferences may be drawntherefrom.

In various embodiments, through use of unobscuring module 146 and/orunconstraining module 147, airlines may implement revisions to theirbooking strategies. In many instances, airlines may take more bookingson marginal flights and/or lower revenue seats than before. Stateddifferently, after assessing the improved estimated demand informationprovided and/or facilitated by unobscuring module 146 and/orunconstraining module 147, airlines may protect fewer upper-class seats,and more bookings in lower classes are thus made. However, the resultingbookings are typically made in fare classes that are higher than wouldhave resulted if forecasts were based on historical demand alone and/orbased on the presumption of fare class demand independence. This isbecause, after assessment of the improved estimated demand information,buy-down risk in higher classes is better known. Additional seats arethus booked in a manner that is revenue-positive for the airline, as (i)seats previously left empty are occupied, and (ii) buy-down is reduced.

In addition to unobscuring principles and/or unconstraining principlesas disclosed hereinabove, forecasting system 115 may be configured toutilize fare adjustment module 148. Fare adjustment module 148 isconfigured to provide insight into the demand relationships between oneor more fare classes. Fare adjustment module 148 can thus be utilized todetermine under what conditions opening a new, lower fare class is arevenue positive decision.

Prior demand forecasting approaches often assumed independence ofdemand; in other words, prior approaches often assumed 0% buy down. Incontrast, principles of the present disclosure contemplate demandforecasting approaches and/or fare adjustment approaches that recognizethat certain passengers may be “product oriented” (i.e., passengers whowill purchase in a higher fare class than the lowest available), whilecertain other passengers may be “price oriented” (i.e., passengers whowill buy down, if given the opportunity to do so).

Because not all passengers are product oriented, and not all passengersare price oriented, opening a new, lower fare class F_(L) has at least 2effects. First, “stimulation”. Stimulation refers to revenue arisingfrom and/or represented by new bookings that would not have occurred ifclass F_(L) had not been opened. Second, a “dilution penalty” or simply“dilution”. Dilution refers to the negative revenue consequences arisingfrom and/or represented by bookings that were bought down in classF_(L), but which would have been purchased in a higher class if classF_(L) was not open. Stated generally, fare adjustment module 148 may beutilized to evaluate if, for a particular set of circumstances, thestimulation of opening class F_(L) exceeds the dilution arising fromopening of class F_(L)—and thus, whether opening class F_(L) is arevenue positive decision.

Prior approaches often considered only the effects of stimulation, anddid not consider dilution; accordingly, prior approaches often led toclass opening decisions that were revenue negative.

It will be appreciated that the ratio of product-oriented passengers (orproduct-oriented demand) to price-oriented passengers (or price-orienteddemand) has a significant effect on fare adjustments. In fare adjustmentmodule 148, “buy-down percent” may be considered to be the percentage ofpassengers for which demand is price-oriented. Fare adjustment module148 may identify, for a particular set of bookings, the associateddemand orientation.

In various embodiments, fare adjustment module 148 is configured toconsider certain bookings (for example, bookings that were revisedand/or restated as a result of operation of unobscuring module 146) tobe price-oriented bookings, as these bookings have already demonstratedbuy-down. Certain other bookings may be determined to be price-oriented,for example based on customer purchase history or other historical data.Bookings which are not determined to be price oriented may be consideredto be product-oriented. An illustration of exemplary ratios ofprice-oriented demand vs. product-oriented demand for a series of fareclasses on a particular flight is illustrated in FIG. 4B. Statedgenerally, the proportion of demand for a fare class that isproduct-oriented demand tends to increase as the expense of the fareclass increases; conversely, the proportion of demand for a fare classthat is price-oriented demand tends to increase as the expensedecreases.

In various embodiments, fare adjustment module 148 is configured toutilize fare adjustment method 400. With reference now to FIG. 4A, inone embodiment fare adjustment method 400 comprises determining abuy-down percentage (step 410), determining a marginal fare (step 420),and determining an adjusted fare (step 430).

In fare adjustment method 400, using restated bookings information fromunobscuring module 146, a buy-down percentage BD % may be calculated asfollows: the ratio of historical bookings in classes higher than thecurrent class that were booked in the lowest available class, or weremoved “up” to a higher fare class via unobscuring, to the total numberof historical bookings in classes higher than the current class. It willbe appreciated that a buy-down percentage may be calculated for a flightor group of flights, for example based on one or more commoncharacteristics of a group of flights. Moreover, BD % may be consideredto be the percent of bookings that are price-oriented bookings.

In fare adjustment method 400, a marginal fare MF may be determined asfollows: MF=(average fare*probability(seat purchased by currentclass))+(LOSS*probability(seat purchased by higher class)), where:

-   -   LOSS is the difference in revenue per booking between the        current class and the parent class (i.e., the average fare of        current class minus the average fare of the parent class);    -   probability(seat purchased by current class)=the demand (current        class), divided by the demand (current class and all higher        classes); and    -   probability(seat purchased by higher class)=1 minus the        probability(seat purchased by current class); the marginal fare        calculation may utilize forward looking demand for a flight or        group of flights.

In fare adjustment method 400, determining an adjusted fare may beimplemented as follows: an adjusted fare AdjF for a particular class maybe equal to (BD %*MF)+(1−BD %)*AF), where AF is the average fare in theclass. It will be appreciated that AdjF may be obtained based at leastin part on a weighted average of average fare and marginal fare based onbuy-down.

In various embodiments, fare adjustment module 148 makes an initialassessment configured to assume 100% buy down. In other words, if alower class is opened, everyone from higher classes will buy down to D.This is illustrated by example in Table 4A. In Table 4A, demand forseats on a hypothetical flight having 125 seats is assumed to bedeterministic, as shown:

TABLE 4A Incremental Cumulative/ Revenue Arising Fare Average Top-DownTotal from Having Class Fare Demand Demand Revenue the Class Open A $40010 10 $4,000 $4,000 B $300 25 35 $10,500 $6,500 C $200 40 75 $15,000$4,500 D $100 50 125 $12,500 ($2,500)

When modeled in this manner, it is apparent that having class D open isnot a revenue positive decision; the true value of each booking in classD (i.e., the marginal fare) is equal to ($2500)/125=($20), a loss oftwenty dollars.

In accordance with various embodiments, fare adjustment module 148 isconfigured to utilize expected marginal seat revenue (EMSR) information,for example EMSR information for each seat in a fare class, in order todetermine whether to open a particular fare class, assign seat protectsto a particular fare class, and/or the like.

In various embodiments, fare adjustment module 148 is configured toassign seat protects via a “partitioned” approach. In a partitionedapproach, seat protects are assigned based on the class of the EMSR. Inother exemplary embodiments, fare adjustment module 148 is configured toassign seat protects via a “nested” approach. In a nested approach, seatprotects are assigned based on the value of the EMSR.

A partitioned approach may calculate the EMSR for a seat based at leastin part on the demand forecast and the average fare for each class. Anested approach may calculate the EMSR based on the demand forecast andthe average fare of a given class, or based on the joint demand forecastand the joint average fare of a given class and all higher classes.

By way of example, fare adjustment module 148 may consider ahypothetical situation wherein 1 seat protect must be allocated. In thishypothetical situation, the seat protect is in B class, which isdetermined to have a 20% chance of booking, and a $900 average fare. TheEMSR for this seat is $900*0.2=$180, which, in this example, is thehighest EMSR remaining for any open seat in any fare class.

When fare adjustment module 148 employs a partitioned approach, the seatprotect is assigned to B class, which is the class used in the EMSRcalculation. An advantage of the partitioned approach is it holds outfor the potential higher value seat booking, thus combatting spiraldown. However, because the chance of booking the seat is somewhat low(i.e., only 20%), the degree to which spiral down is reduced may besmall. Moreover, a potential downside of the partitioned approach is theseat protect in B class will cause potential bookings in lower classesto be rejected, even if those potential bookings have a higher actualvalue than the EMSR of $180 for this B class seat.

Continuing with this example, when fare adjustment module 148 employs anested approach, the seat protect is assigned to D class (which is theclass having a value equal to the EMSR value of $180) rather than to Bclass, which has a value of $900. The nested approach ensures that anybooking having a value higher than the probabilistic value of theprotected seat will be accepted. However, the nested approach does nottake dilution into account; the forecasted class B customer mightpurchase in class D instead (i.e., the customer might buy down).

In order to address the potential downsides and/or shortcomingsillustrated by the foregoing examples, in various embodiments fareadjustment module 148 is configured to account for, estimate, and/orotherwise model or respond to dilution.

In a further example shown in Table 4B, operation of fare adjustmentmodule 148 is illustrated.

TABLE 4B Cumulative/ Loss if Seat Probability seat Probability seatExpected value Fare Average Top-Down Purchased by purchased by purchasedby accounting for Class Fare Demand Demand higher class current classhigher class dilution A $300 5 5 N/A 100%  0% $300 B $200 15 20 −$10075% (15/20) 25% $125 C $100 30 50 −$100 60% (30/50) 40% $20 D $40 50 100   −$60-  50% (50/100) 50% −$10

In the example scenario illustrated in Table 4B, fare adjustment module148 determines that having class D open is not a revenue positivedecision. Stated differently, the true value of a class D booking (themarginal fare) is the expected value received from a class D bookingwhen class D is open: marginal fare=$40*(50/100)+(−$60)*(50/100)=$−10.As can be seen, a class D booking results in: $40*(50/100)=$20 of“stimulus”, and (−$60)*(50/100)=−$30 in “dilution”.

In various embodiments, in connection with operation of fare adjustmentmodule 148 and/or forecasting system 115, a seat allocation system isutilized to allocate seats in a class until the joint EMSR value fallsbelow the average fare of the child class. Fare adjustment module 148may be utilized to modify the seat allocation process for a particularclass to account for dilution if a child class is open. Afterutilization of fare adjustment module 148, a seat allocation system mayallocate seats in a class until the joint EMSR value falls below theadjusted average fare of the child class. With reference now to FIG. 4C,it can be seen that, responsive to operation of fare adjustment module148, a seat allocation system may assign more seats to a particularclass than would otherwise be assigned; stated differently, a seatallocation system may assign more seats to the current class and fewerseats to a child class.

For example, in a particular example instance illustrated in FIG. 4C,absent operation of fare adjustment module 148, only six seats would beallocated to the current fare class (shown at point A in FIG. 4C). Incontrast, responsive to operation of fare adjustment module 148, nineseats are allocated to the current fare class (shown at point B in FIG.4C). In other words, three additional seats that would otherwise havebeen allocated to a child class are instead allocated to the currentclass. In this manner, because additional seats are allocated to thecurrent class and fewer seats are thus available for allocation to achild class, the risk of future buy-down is reduced. In sum, fareadjustment module 148 enables proper valuation of a child class ascompared to the parent class, accounting for both stimulation anddilution.

It will be appreciated that if all passengers were product oriented,prior approaches which presumed independence of demand would beaccurate; however, because all passengers are not product oriented, fareadjustment module 148 may be utilized to better quantify the revenueeffects of opening a particular fare class for bookings. Moreover, itwill be appreciated that fare adjustment module 148 may not necessarilybe utilized to set availability or fares for a particular fare class.Rather, fare adjustment module 148 may typically be utilized todetermine the true value of the child class for purposes of comparisonto the parent class. Revised and/or updated solutions may be generatedbased at least in part on the output of fare adjustment module 148. Suchupdated solutions may be utilized by other systems, for example arevenue management system, to set and/or revise actual fare class seatprices for public sale. Moreover, in various exemplary embodiments, theoutput of fare adjustment module 148 may be utilized as an input toother electronic systems (for example, PROS), for example in order torefine and/or revise a demand forecast and/or optimization.

In addition to fare adjustment principles, unobscuring principles,and/or unconstraining principles as disclosed hereinabove, forecastingsystem 115 may be configured to utilize prime class remapping (PCR)module 149. In various exemplary embodiments, PCR module 149 isconfigured to allocate prime class bookings to fare classes in a mannerthat results in positive revenue consequences (or reduces and/orminimizes negative revenue consequences).

Typically, airlines have at least one fare class (referred to herein asa “prime class”) that is given priority over all (or some) other fareclasses. Certain prime class contracts also require last seatavailability. Because prime class bookings often occur close to a flightdeparture date, prime class bookings often displace high-revenue fareclass bookings. However, prime class bookings are often associated witha revenue amount that is inconsistent with the position they occupy inthe class hierarchy. Stated another way, prime class bookings oftenresult in zero additional revenue (for example, prime class bookingsarising from use of mileage rewards programs, such as high-prioritydouble mileage redemptions) or minimal additional revenue (certaingovernment and/or corporate bookings), but have high priority. Ingeneral, because prime class bookings have a lower average fare thanmost fare classes, protecting seats for prime class bookings at theexpense of other revenue bookings has a negative impact on airlinerevenue. Prime class bookings have high priority, but highly variablerevenue; accordingly, while airlines are often obligated to protectseats for prime class bookings, doing so typically has a negative effecton revenue.

Adding complexity to this problem, common forecasting tools in theairline industry are not configured to handle prime class forecasting; atypical approach is simply not to forecast prime class demand at all,but rather to assume prime class demand is zero. However, because primeclass bookings commonly occupy from about 1% to about 3% of totalbookings, ignoring demand for prime class bookings introducesforecasting errors, resulting, depending on the nature of the errors, inunnecessary buy-down and/or empty (spoiled) seats on a flight.

Turning now to FIG. 5, in accordance with various embodiments PCR module149 is configured to implement a method 500 for prime class remapping.Stated generally, PCR module 149 is configured to provide an improvedanswer to the question: “What is the value of a particular prime classbooking?”

In various embodiments, PCR module 149 is configured to treat a primeclass booking as if it were a booking of an equivalent revenue class orhigher class. Stated differently, PCR module 149 is configured for“remapping” of prime class bookings into other fare classes, for examplefor purposes of demand forecasting, seat protection, and/or the like.

In various embodiments, prime class remapping method 500 utilizes anaverage fare for prime class bookings. In other exemplary embodiments,method 500 utilizes a known fare for each prime class booking. Incertain exemplary embodiments, method 500 employs a hybrid approach,wherein certain prime class bookings are considered to represent anaverage prime class fare, and certain other prime class bookings areconsidered to represent a known prime class fare (which may be higher orlower than the average).

PCR module 149 and/or method 500 may be utilized on any suitable timeschedule, as desired. For example, PCR module 149 may be operable aftercollection of data associated with a DCP, on a weekly basis, on a dailybasis, on an hourly basis, on a “triggered” basis (for example, eachtime a trigger event occurs, such as a prime class booking), and/or thelike.

In various embodiments, PCR module 149 identifies the net prime classbookings for a particular flight for the period in question (step 510),as follows: net prime class bookings=current prime class bookings—priorprime class bookings. For each net prime class booking, PCR module 149identifies the fare class that is closest in value to the value (i.e.,average or known) of that net prime class booking (step 520). Thisclosest fare class may be referred to as the “floor class”. However, forthe flight in question, at the time of that prime class booking thefloor class and/or higher fare classes may have been (or are) closed. Ifthe floor class was or is closed, PCR module 149 identifies analternative class, the “displacement class” (step 530). The displacementclass is the lowest class that is both (i) higher than the floor class,and (ii) currently open for bookings. PCR module 149 “remaps” each primeclass booking to its respective target class, which is the higher of thefloor class and the displacement class for that prime class booking(step 540). PCR module 149 may also add the remapped net prime bookingsto other booking information for the current period and/or priorperiod(s), for example in order to generate cumulative bookinginformation for the current period (step 550). Additionally, if apreviously booked prime class booking has been cancelled during thecurrent period, PCR module 149 may “unmap” that prime class booking fromthe lowest fare class that had previously received any remapped primeclass booking (step 560).

It will be appreciated that any suitable data inputs and/or informationmay be utilized by PCR module 149, for example historical bookinginformation, estimated fare information for a prime class booking,actual fare information for a prime class booking, currently open fareclasses for a flight, prior output of PCR module 149 for a prior timeperiod, departure date information, market information, fareinformation, and/or the like.

Operation of PCR module 149 and/or method 500 may be illustrated in theexample shown in Table 5A. For a particular example, for Flight 544during a particular time period, 5 new prime class bookings arereceived. For 3 of the new prime class bookings (prime class bookingsP1, P2, and P3), class K is the floor class; for the remaining 2 primeclass bookings (P4 and P5), class L is the floor class. PCR module 149remaps prime class bookings P1 through P3 into class T (the lowest openclass higher than the floor class, class K, which is closed). PCR module149 remaps prime class bookings P4 and P5 into class L. PCR module 149outputs the updated remapped prime class booking information in the formof an updated bookings table. The updated bookings table may be used,for example, by other components of forecasting system 115, externalsystem(s) 160, and/or the like.

TABLE 5A New Prime Class Remapped Prime Fare Class Bookings ClassBookings Prime 5 N/A Q N/A 0 N N/A 0 V N/A 0 W N/A 0 L N/A 2 S N/A 0 TN/A 3 G (closed) N/A N/A K (closed) N/A N/A U (closed) N/A N/A E(closed) N/A N/A R (closed) N/A N/A

Principles of operation of PCR module 149 and/or method 500 are furtherillustrated in the additional example represented in Table 5B. For aparticular example Flight 544, during a particular time period, 3 primeclass bookings are cancelled, i.e., “new” prime class bookings has thevalue −3. In this example, 10 prior prime class bookings had previouslybeen remapped into fare classes T, S, L, W, and V, with 2 prime classbookings previously remapped into each class, respectively. −3 primeclass bookings were received in the current period, so 2 previouslyremapped prime class bookings are “unmapped” from fare class T (thelowest fare class that had previously received prime class remapping).Fare class T now holds 0 remapped prime class bookings, so the 1remaining prime class cancellation is allocated to fare class S (thenext lowest fare class that had previously received prime classremapping). PCR module 149 outputs the updated remapped prime classbooking information, for example for use by other components offorecasting system 115, external system(s) 160, and/or the like.

TABLE 5B Previously Updated Remapped “New” Prime Class Remapped PrimePrime Class Fare Class Bookings Class Bookings Bookings Prime −3 N/A N/AQ N/A 0 0 N N/A 0 0 V N/A 2 2 W N/A 2 2 L N/A 2 2 S N/A 2 1 T N/A 2 0 G(closed) N/A N/A N/A K (closed) N/A N/A N/A U (closed) N/A N/A N/A E(closed) N/A N/A N/A R (closed) N/A N/A N/A

Via use of PCR module 149 and/or method 500, forecasting system 115 canbetter account for, modify, and/or forecast prime class demand.Additionally, because prime class bookings have been “remapped” to otherfare classes that are suitable for use in external forecasting tools(for example, PROS), forecasting system 115 output may be utilized toincorporate prime class demand into an overall demand model for all fareclasses for a particular flight. Via operation of PCR module 149 and/ormethod 500, forecasting system 115 is also enabled to reduce and/orprevent displacement of high value, late bookings by prime classbookings (which cannot be prevented from booking). Yet further,forecasting system 115 is enabled to more accurately account for thevalue of a particular prime class booking to an airline. In this manner,forecasting system 115 increases revenues (and/or decreases losses)associated with prime class bookings.

It will be appreciated that principles of the present disclosureassociated with PCR module 149 and/or method 500 are not limited toprime class bookings. More generally, remapping approaches similar tothose disclosed herein may suitably be employed to remap (and/orotherwise adjust and/or compensate for) any booking that is capable ofbeing assigned to a fare class having a value that is higher than thevalue (actual or estimated) of that booking.

While the exemplary embodiments described herein are described insufficient detail to enable those skilled in the art to practiceprinciples of the present disclosure, it should be understood that otherembodiments may be realized and that logical and/or functional changesmay be made without departing from the spirit and scope of the presentdisclosure. Thus, the detailed description herein is presented forpurposes of illustration and not of limitation.

For the sake of brevity, conventional data management, computernetworking, statistical assessment, software application development,and other aspects of exemplary systems and methods (and componentsthereof) may not be described in detail herein. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent functional relationships and/or physical orcommunicative couplings between the various elements. It should be notedthat many alternative or additional functional relationships or physicalconnections may be present in a practical forecasting system.

While the description references specific technologies, systemarchitectures and data management techniques, practitioners willappreciate that this description is of various embodiments, and thatother devices and/or methods may be implemented without departing fromthe scope of principles of the present disclosure. Similarly, while thedescription references a user interfacing with the system via a computeruser interface, practitioners will appreciate that other interfaces mayinclude mobile devices, kiosks and handheld devices such as mobilephones, smart phones, tablet computing devices, etc.

While the steps outlined herein represent exemplary embodiments ofprinciples of the present disclosure, practitioners will appreciate thatthere are any number of computing algorithms and user interfaces thatmay be applied to create similar results. The steps are presented forthe sake of explanation only and are not intended to limit the scope ofthe present disclosure in any way. Benefits, other advantages, andsolutions to problems have been described herein with regard to specificembodiments. However, the benefits, advantages, solutions to problems,and any element(s) that may cause any benefit, advantage, or solution tooccur or become more pronounced are not to be construed as critical,required, or essential features or elements of any or all of the claims.

Systems, methods and computer program products are provided. In thedetailed description herein, references to “various embodiments”, “oneembodiment”, “an embodiment”, “an example embodiment”, etc., indicatethat the embodiment described may include a particular feature,structure, or characteristic, but every embodiment may not necessarilyinclude the particular feature, structure, or characteristic. Moreover,such phrases are not necessarily referring to the same embodiment.Further, when a particular feature, structure, or characteristic isdescribed in connection with an embodiment, it is submitted that it iswithin the knowledge of one skilled in the art to effect such feature,structure, or characteristic in connection with other embodimentswhether or not explicitly described. After reading the description, itwill be apparent to one skilled in the relevant art(s) how to implementprinciples of the disclosure in alternative embodiments.

It should be understood that the detailed description and specificexamples, indicating exemplary embodiments, are given for purposes ofillustration only and not as limitations. Many changes and modificationsmay be made without departing from the spirit thereof, and principles ofthe present disclosure include all such modifications. Correspondingstructures, materials, acts, and equivalents of all elements areintended to include any structure, material, or acts for performing thefunctions in combination with other elements. Reference to an element inthe singular is not intended to mean “one and only one” unlessexplicitly so stated, but rather “one or more.” Moreover, when a phrasesimilar to “at least one of A, B, or C” or “at least one of A, B, and C”is used in the claims or the specification, the phrase is intended tomean any of the following: (1) at least one of A; (2) at least one of B;(3) at least one of C; (4) at least one of A and at least one of B; (5)at least one of B and at least one of C; (6) at least one of A and atleast one of C; or (7) at least one of A, at least one of B, and atleast one of C.

We claim:
 1. A method comprising: determining, by a processor, whichfare classes in a plurality of fare classes have demand that is obscureddue to an availability of seats for booking in a lower fare class in theplurality of fare classes; calculating, by the processor, an unobscureddemand for a fare class in the plurality of fare classes; generating, bythe processor, an unobscured demand forecast for a flight; and opening,by the processor, an additional fare class on the flight for seatbookings, based on the unobscured demand forecast.
 2. The method ofclaim 1, further comprising: converting, by the processor, theunobscured demand for the fare class into integer values representingthe seat bookings in respective fare classes; and updating, by theprocessor, a bookings table with the integer values to form anunobscured bookings table.
 3. The method of claim 1, wherein theplurality of fare classes are configured with parent-childrelationships, and wherein, in the calculating the unobscured demand:the unobscured demand for a child class is used as the upper bound foran EM algorithm as applied to a parent class, top-down bookings for aclass in question are used as the lower bound for the EM algorithm asapplied to the parent class, and the EM algorithm is iterativelyexecuted by the processor until a convergent solution for the unobscureddemand is obtained for the fare class.
 4. The method of claim 3, whereinthe EM algorithm is iterated at least 10 times to obtain the convergentsolution for the unobscured demand.
 5. The method of claim 1, furthercomprising combining, by the processor, an unobscured bookings tablewith an historical bookings table to form a revised historical bookingstable.
 6. The method of claim 1, wherein the unobscured demand forecastis used by at least one of a reservation system or a revenue managementsystem to determine whether to open the additional fare class for theseat bookings.
 7. The method of claim 1, wherein the determining thefare classes for which demand is obscured further comprises: converting,by the processor, a bookings table into a top-down format; identifying,by the processor, a lowest fare class for which the seat bookings werereceived in a first time period; identifying as an obscured class, bythe processor, a parent class of the lowest fare class for whichbookings were received; and identifying as the obscured class, by theprocessor, the fare classes in the plurality of fare classes that arehigher than the parent class of the lowest fare class for which the seatbookings were received.
 8. The method of claim 3, wherein the EMalgorithm comprises:expBkgs=mean+(stdev*stdev)*(pdfLower−pdfUpper)/(cdfUpper−cdfLower);where: the expBkgs is an expectation of the seat bookings in a currentfare class known as unobscured seat bookings; an upperBound is an upperbound of the unobscured seat bookings in the current fare class; alowerBound is a lower bound of the unobscured bookings in a currentclass; the mean is a mean of the seat bookings for the current fareclass in a cohort to which the flight belongs; the stdev is a standarddeviation of the seat bookings for the current fare class in the cohortto which the flight belongs; the cdfUpper is a cumulative distributionfunction of the upperBound; the cdfLower is a cumulative distributionfunction of the lowerBound; the pdfUpper is a probability densityfunction of the upperBound; and the pdfLower is a probability densityfunction of the lowerBound.
 9. The method of claim 1, wherein thecalculating the unobscured demand for the fare class is terminated upondetermining, by the processor, that the unobscured demand for a currentfare class rounds to zero.
 10. The method of claim 1, further comprisingweighting, by the processor, the unobscured demand for the fare class bya weighting parameter.
 11. The method of claim 10, wherein the weightingparameter is determined based at least partially on a departure date ofthe flight.
 12. The method of claim 10, wherein the weighting parameteris determined based at least partially on a departure date of the flightbeing a holiday or a weekend.
 13. The method of claim 1, furthercomprising accessing, by the processor, a bookings table, wherein thebookings table further contains forecasted demand for the flight, andwherein the fare class in the plurality of fare classes is closed andcontains none of the seat bookings; determining, by the processor andusing the seat bookings and the forecasted demand, a monetarystimulation value of opening a closed class; determining, by theprocessor and using the seat bookings and the forecasted demand, amonetary dilution penalty of opening the closed class; and generating,by the processor, booking instructions based on the monetary stimulationvalue and the monetary dilution penalty.
 14. The method of claim 1,further comprising: accessing, by the processor, a bookings table,wherein the bookings table further contains information representing anet prime class seat booking for the flight, and wherein the net primeclass seat booking occurred during a first time period; determining, bythe processor, a floor class for the net prime class seat booking in thebookings table; determining, by the processor, a displacement class fora net prime class seat bookings in the bookings table; determining, bythe processor, a target class for the net prime class seat bookings inthe bookings table, wherein the target class is the higher of the floorclass and the displacement class; and remapping, by the processor, thenet prime class seat bookings in the bookings table into the targetclass to form a remapped bookings table.
 15. The method of claim 1,further comprising: determining, by the processor, the fare classes inthe plurality of fare classes for which demand is constrained in anunobscured bookings table; calculating, by the processor, anunconstrained demand for each constrained fare class in the plurality offare classes; converting, by the processor, the unconstrained demand foreach fare class into integer values representing the seat bookings inthe respective fare classes; updating, by the processor, the unobscuredbookings table with the integer values to form an unconstrained bookingstable; generating, by the processor, an unconstrained demand forecastfor the flight based on the unconstrained bookings table; and opening,by the processor, the additional fare class on the flight for the seatbookings, based on the unconstrained demand forecast.
 16. The method ofclaim 15, further comprising taking, by the processor, a seat booking inthe additional fare class.
 17. The method of claim 15, wherein thedetermining the fare classes for which demand is constrained comprisesidentifying the fare classes that were opened for the seat bookingsduring a particular time interval.
 18. The method of claim 15, furthercomprising weighting, by the processor, the unobscured demand for thefare class by a weighting parameter.
 19. The method of claim 18, whereinthe weighting parameter is determined based at least partially on adeparture date of the flight.
 20. The method of claim 1, wherein abookings table represents actual seat bookings for the flight, andwherein the actual seat bookings are grouped into the plurality of fareclasses.